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941.
Economic transition in central and eastern Europe (CEE) has had a particularly strong impact on industrial cities and regions. Following their economic collapse, most of them are now confronted with serious problems such as high unemployment and vast ecological damage. The paper presents findings from a pan European research project that investigated the problems of these cities and regions as well as the strategies being adopted to cope with structural change. It examines the differences in approaches and addresses the question whether existing EU policy is suitable for supporting the redevelopment of old industrial cities and regions in CEE countries. The paper concludes with recommendations for future directions in policy making. 相似文献
942.
根据△-∑AD转换器原理,通过编程将给定的输入信号转换为1位串行△-∑数据流。用此数据流可以仿真地震数据采集器中的滤波抽样过程,检验设计构造的各级滤波参数能否满足地震观测的需要。为了证明该仿真程序的正确性,本文介绍了利用CS5376A公布的数字滤波参数对数据流进行滤波验证。 相似文献
943.
在北京、天津、河北二市一省部分地区抽样调查了13口井水位、11口井水温、5口井气氡、2口井气汞、2口井氦气数字化观测现状,统计分析了其数据完整率及观测断记次数与数据缺失量;在调查观测数据断记及其原因的基础上,进一步统计分析了数据缺失的主要原因,分析了连续完整的数据系列在地震前兆监测中的有效性。研究结果表明,除了氦气之外,水位、水温、气氡与气汞4大主要测项的运行,总体上是正常的;但多数井多数测项存在断记与数据缺失的问题,其主要原因是仪器故障与运行不正常,其次是停电、通信线路故障与雷击,此外还存在原因不明的断记与缺数的问题;以井统计,约有1/2的水位与水温观测井可在地震中期与短临前兆中发挥作用,而气氡、气汞等化学量观测只在地震短临前兆监测中,约有一半的井有可能发挥一定效能。 相似文献
944.
Analysis and modeling of the seasonal South China Sea temperature cycle using remote sensing 总被引:1,自引:0,他引:1
Daniel J. Twigt Erik D. De Goede Ernst J. O. Schrama Herman Gerritsen 《Ocean Dynamics》2007,57(4-5):467-484
The present paper describes the analysis and modeling of the South China Sea (SCS) temperature cycle on a seasonal scale.
It investigates the possibility to model this cycle in a consistent way while not taking into account tidal forcing and associated
tidal mixing and exchange. This is motivated by the possibility to significantly increase the model’s computational efficiency
when neglecting tides. The goal is to develop a flexible and efficient tool for seasonal scenario analysis and to generate
transport boundary forcing for local models. Given the significant spatial extent of the SCS basin and the focus on seasonal
time scales, synoptic remote sensing is an ideal tool in this analysis. Remote sensing is used to assess the seasonal temperature
cycle to identify the relevant driving forces and is a valuable source of input data for modeling. Model simulations are performed
using a three-dimensional baroclinic-reduced depth model, driven by monthly mean sea surface anomaly boundary forcing, monthly
mean lateral temperature, and salinity forcing obtained from the World Ocean Atlas 2001 climatology, six hourly meteorological
forcing from the European Center for Medium range Weather Forecasting ERA-40 dataset, and remotely sensed sea surface temperature
(SST) data. A sensitivity analysis of model forcing and coefficients is performed. The model results are quantitatively assessed
against climatological temperature profiles using a goodness-of-fit norm. In the deep regions, the model results are in good
agreement with this validation data. In the shallow regions, discrepancies are found. To improve the agreement there, we apply
a SST nudging method at the free water surface. This considerably improves the model’s vertical temperature representation
in the shallow regions. Based on the model validation against climatological in situ and SST data, we conclude that the seasonal
temperature cycle for the deep SCS basin can be represented to a good degree. For shallow regions, the absence of tidal mixing
and exchange has a clear impact on the model’s temperature representation. This effect on the large-scale temperature cycle
can be compensated to a good degree by SST nudging for diagnostic applications. 相似文献
945.
Analysis of Fog Probability from a Combination of Satellite and Ground Observation Data 总被引:1,自引:0,他引:1
The Cloud Type product, developed by the Satellite Application Facility to support to nowcasting and very short-range forecasting
(SAFNWC) of EUMETSAT and based on Météosat-8/SEVIRI, identifies cloud categories, and especially low and very low clouds which
are first estimates of areas where fog is likely to occur. This cloud type is combined with precipitation information from
radar data and with hourly diagnostic analyses of 2-metre relative humidity and 10-metre wind to elaborate an hourly analysis
of fog probability. This analysis provides four levels of fog probability with a 3-kilometre horizontal resolution: No risk,
low-level risk, medium-level risk and high-level risk. An evaluation of such fog probability analyses versus a one-year set
of French hourly SYNOP reports shows encouraging results (potential of detection = 0.73 for low and medium and high-level
risks), even if false alarm ratios remain high. Most of the non-detections occur at twilight and are due to satellite non-detections.
Eventually, we show case studies that clearly illustrate the high potential of the method. 相似文献
946.
基于网络的煤田地质资料信息管理系统的设计与开发 总被引:1,自引:0,他引:1
煤田地质资料是地质信息资源的载体,传统的资料管理模式已不能满足当代数字化和信息化社会的发展需求。利用SqlServer数据库,在ASP.net技术的支持下,借助MapXtreme2004平台,建立了青海省煤田地质资料信息管理系统。该系统采用B/S结构,实现了煤田地质资料的属性和图形的联合查询,以及各种类型的资料在Web浏览器中查阅。 相似文献
947.
948.
Jean S. Kane Philip J. Potts Thomas Meisel Michael Wiedenbeck 《Geostandards and Geoanalytical Research》2007,31(3):285-288
The International Association of Geoanalysts (IAG) published a protocol for the certification of reference materials in close accord with the International Organisation for Standardisation (ISO) guidelines (Kane et al. 2003). This article supplements that protocol, providing additional discussion of best approaches for pre-selecting laboratories for participation in certification projects. This discussion also makes a distinction between inter-laboratory certifications, where n = 15 is the general standard, and expert laboratory certifications, where a much smaller number of laboratories will be deemed qualified to provide data of the quality needed for certification. 相似文献
949.
Kriging Regionalized Positive Variables Revisited: Sample Space and Scale Considerations 总被引:1,自引:0,他引:1
Frequently, regionalized positive variables are treated by preliminarily applying a logarithm, and kriging estimates are back-transformed
using classical formulae for the expectation of a lognormal random variable. This practice has several problems (lack of robustness,
non-optimal confidence intervals, etc.), particularly when estimating block averages. Therefore, many practitioners take exponentials
of the kriging estimates, although the final estimations are deemed as non-optimal. Another approach arises when the nature
of the sample space and the scale of the data are considered. Since these concepts can be suitably captured by an Euclidean
space structure, we may define an optimal kriging estimator for positive variables, with all properties analogous to those
of linear geostatistical techniques, even for the estimation of block averages. In this particular case, no assumption on
preservation of lognormality is needed. From a practical point of view, the proposed method coincides with the median estimator
and offers theoretical ground to this extended practice. Thus, existing software and routines remain fully applicable. 相似文献
950.
A modified counter propagation network model and an extended self-organizing map model have the same three-layer network architecture
while employing slightly different learning rules. Their network architecture comprises an input layer, a Kohonen layer and
an output layer. The neurons between two neighboring layers are fully connected and the neighboring neurons within the Kohonen
layer also have neighborhood connections. The modified counter propagation network model employs the Kohonen algorithm to
train the Kohonen layer while using the Widrow–Hoff rule to train the output layer. However, the extended self-organizing
map model applies a modified Kohonen’s learning rule to train both the Kohonen layer and the output layer. This paper compares
the performances of these two models in supervised classification of remotely sensed data. The training results show that
compared to the extended self-organizing map model, the modified counter propagation model has faster learning speed but larger
output errors. The classification results indicate that the extended self-organizing map model has a faster classification
speed and a much higher classification precision than the modified counter propagation model. 相似文献